Smart electrical outlets and associated networks

ABSTRACT

A control system ( 300 ) allows recognized standard premise electrical outlets, for example NEMA, CEE and BS, among others to be remotely monitored and/or controlled, for example, to intelligently execute blackouts or brownouts or to otherwise remotely control electrical devices. The system ( 300 ) includes a number of smart receptacles ( 302 ) that communicate with a local controller ( 304 ), e.g., via power lines using the TCP/IP protocol. The local controller ( 304 ), in turn, communicates with a remote controller ( 308 ) via the internet.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. patent application Ser. No.13/757,156, entitled, “SMART ELECTRICAL OUTLETS AND ASSOCIATEDNETWORKS,” filed Feb. 1, 2013, which is a continuation U.S. patentapplication Ser. No. 12/569,377, entitled, “SMART ELECTRICAL OUTLETS ANDASSOCIATED NETWORKS,” filed Sep. 29, 2009, which is a continuation ofU.S. patent application Ser. No. 12/531,226, entitled, “SMART ELECTRICALOUTLETS AND ASSOCIATED NETWORKS,” filed on Feb. 16, 2010, which claimsthe benefit of U.S. National Stage of PCT/US2008/057150, entitled,“SMART NEMA OUTLETS AND ASSOCIATED NETWORKS,” filed on Mar. 14, 2008,which in turn claims priority to U.S. Provisional Application No.60/894,846, entitled, “SMART NEMA OUTLETS AND ASSOCIATED NETWORKS,”filed on Mar. 14, 2007. The contents of all of the above-notedapplications are incorporated herein by reference as if set forth infull and priority to these applications is claimed to the full extentallowable under U.S. law and regulations.

FIELD OF INVENTION

The present invention relates generally to electrical power distributionand management and, in particular, to an electrical outlet, or otherdevice associated with a local (e.g., single or multiple residential orbusiness premises) circuit, to intelligently monitor at least a portionof the circuit and control delivery of electricity over the circuit.

BACKGROUND OF THE INVENTION

Power distribution and electrical distribution are monitored andcontrolled for a variety of purposes. In this regard, power distributiongenerally refers to transmission between a power plant and substationswhereas electrical distribution refers to delivery from a substation toconsumers. Electricity is further distributed within consumer premisestypically via a number of local circuits.

Power distribution may be monitored and controlled in relation toaddressing actual or potential over capacity conditions. Such conditionshave become increasingly common in the United States and elsewhere dueto increasing industrial and residential power needs coupled with agingpower infrastructure and practical limitations on new power generation.Over capacity conditions are often addressed by reducing or interruptingpower provided to standard residential and commercial consumers, e.g.,blackouts or brownouts. For example, during periods of peak usage, arolling blackout may be implemented where power to grid subdivisions issequentially interrupted to reduce the overall load on the grid.

The effects of such power interruptions can be ameliorated to someextent. Certain critical or high value customers may be exempted fromrolling blackouts if the structure of the grid allows. Other criticalfacilities or equipment may be supported by generators or redundant,fail-safe power supplies. However, for many standard customers, powerinterruptions, and the consequences thereof to data systems and othervulnerable products, is simply endured. For these consumers, theinterruptions are indiscriminate and, in many cases, total.

Electrical distribution is also monitored and controlled including atthe internal premises level. For example, fuses, circuit breakers,ground fault indicators, surge protectors and the like are generallyemployed to interrupt or damp electricity on a circuit in the event thatthe current drawn by the circuit exceeds a prescribed level. Theseelements are typically required by code and may be customized to someextent, for example, with respect to circuits for supplying high (e.g.dryers, air conditioners) or low (e.g., lighting) power devices.However, these elements are generally unintelligent and limited tohazard avoidance. They typically do not recognize devices or devicetypes when connected to a circuit, do not allow for addressing largergrid needs and are not sufficiently responsive for addressing certainsafety issues such as potential electrocutions.

SUMMARY OF THE INVENTION

The present invention relates to intelligent circuit devices such aselectrical outlets, e.g., standard NEMA or other electrical standard(e.g. Consortium for Energy Efficiency [CEE], British Standard [BS],etc.) outlets, and to customer premises electrical systems, appliances,power distribution systems and associated processes that may utilizesuch smart circuit devices. The smart circuit devices of the presentinvention can monitor a load connected to a circuit and controldistribution of power via the circuit. The circuit devices can also becontrolled via a communications interface so as to implement a local orgrid policy concerning electrical delivery or usage. In this manner,power can be distributed more efficiently, outlet and building wiringsafety can be enhanced and electrical grid capacity problems can beaddressed more effectively. Also, the invention delivers security andconvenience features.

In accordance with one aspect of the present invention, a utility(including a system and associated functionality) is provided forenabling network messaging such as Transmission ControlProtocol/Internet Protocol (TCP/IP) communication to an outletreceptacle, e.g., a standard NEMA or other standard outlet receptacle.In this manner, the receptacle effectively becomes a client or datanetwork node. This enables a wide variety of functionality. For example,the outlet receptacles can operate as intelligent control points forelectrical distribution, providing feedback concerning the types ofdevices that are currently plugged into the receptacles and selectivelycontrolling the delivery of electricity via the receptacles (includingreducing power consumption by eliminating individual power waveformcycles delivered via the receptacles via fast on/off switching orotherwise periodically interrupting or limiting power consumption). Inaddition, the receptacles can be controlled via a local area network,wide area network or other network using network protocols such asTCP/IP communications or other network protocols, such protocolstransmitted via wired (including over local premise power wiring, cableTV data network, DSL, etc.) or wireless (802.11, Bluetooth, satellite,etc.) means so as to enable remote or intelligent operation of devicesthat are not otherwise adapted for data network control. The receptaclecommunication technology also provides a convenient mechanism forintelligent devices to communicate via power lines to a wide areanetwork and facilitates standardization of such devices.

In this regard, though any network messaging protocol could be utilized,TCP/IP currently has a number of advantages including the following:

1. TCP/IP is the preferred protocol for communicating to the receptaclesfor both technical and economic reasons.

2. TCP/IP is the standard protocol on the internet, the largest networkon the planet. It is an open protocol and very unlikely to be replaced.

3. TCP implementations and supporting infrastructure continue toimprove. In particular, it is now possible to get very small andlightweight implementations of TCP suitable for the processing powerthat can be easily embedded in a heat limited small space such as areceptacle box.

4. The overwhelming adoption of TCP/IP is driving the cost point of TCPinfrastructure devices down and down. This is a very strong reason tochoose it.

In accordance with another aspect of the present invention, a utility isprovided for controlling delivery of power via a local (e.g.,on-premises) circuit device such as a receptacle or group of receptaclesbased on a load analysis. Specifically, the utility involves monitoringat least one local circuit device to determine information regarding aloading of the local circuit device based on an analysis (e.g., digitalprocessing) of an electrical signal transmitted via the circuit device,and controlling delivery of power via the circuit device based on theanalysis. The analysis may be implemented by a digital processor at thecircuit device such as at an outlet or at another location (e.g., at acircuit breaker panel or elsewhere on a controlled circuit). Forexample, different electrical devices or appliances may producedifferent electrical signatures that can be detected at a receptacle.Accordingly, the electrical signal can be analyzed to determine aclassification of an electrical device, e.g., to identify the specificelectrical device or the type of electrical device (or an intelligentdevice can identify itself), to set power delivery policies (e.g., basedon monitored usage patterns), to identify power delivery quality issues(in either the power supplied or the electrical wiring), to providevirtual Ground Fault Circuit Interruption (GFCI) functionality inspecified receptacles as needed by comparing summary currentmeasurements to neutral current, or to identify a loading anomaly orsafety issue. This information may be used to, for example, reduce thepower delivered to the device (e.g., via rapid switching to eliminateselected cycles of the power signal or by interrupting power to thedevice for a given time period(s)) or to assign the device/receptacle apriority level in the event of power reduction (e.g., a brownout).Alternatively, the digital analysis may indicate a short circuit, apotential shock or electrocution event or other safety concern. In suchcases, power to the receptacle may be interrupted. Also, if a deviceswitch is not supposed to be on, e.g., if the resident is on vacationand a light is suddenly turned on, a security alert can be generated aswell as an email alert.

Relatedly, a fast power switching function can be implemented to controlpower delivery. Such fast switching structure can be used in at leasttwo ways: 1) arc suppression when turning on/off main relays; and 2)fast switching when “stealing” cycles. Traditional mechanical switchingrelays are generally not viewed as appropriate for the latter functiondue to the speed of operation required. Rather, this may be accomplishedby solid state switching such as triacs or MOS devices. More generally,the desired attributes for this switching function include: the switchgenerally needs to handle high current environments (in contrast to manymicroelectronic environments); and the switch should present a lowvoltage drop thus producing heat at a lower rate. It has been recognizedthat heat generation may be problematic, particularly in relation toimplementations where the switching function is executed in an outletbox or in other constrained, unventilated contexts. In order to minimizeheat production, a fast switching device (e.g., semiconductor powerswitch) may be used in conjunction with a traditional mechanical relay,each controlled by a combination of analog and digital circuitry. Inthis manner, the fast switching times needed to support the requirementsof this system can be attained, while the mechanical relay provides thenecessary low speed switching and low heat production. The semiconductorswitching devices (e.g., triacs, Metal Oxide Semiconductors, etc.) arefast but will produce some heat. The mechanical relays are relativelyslow but produce little heat. When operated in conjunction with eachother under microprocessor or other digital means control, the twoswitching devices can provide the necessary fast switching withacceptable levels of heat production. Alternatively, a fully solid stateswitching device may be used while addressing the desired attributesnoted above. It will be appreciated, though, that the desired switch isfaster than traditional mechanical switching devices, and involveshigher power signals than many conventional solid state switches, butalso does not require the speed of some conventional solid stateswitches. It is expected that a variety of solutions may thus bedevised.

Relatedly, according to a further aspect of the present invention, areceptacle can be used either to selectively interrupt power supply orto selectively deliver power to associated electrical devices or loads.In the latter regard, it may be desired to selectively deliver power forvarious reasons including to supply power in accordance with a policy,to supply power in accordance with an inferred or otherwise known usagepattern, or to monitor an idle device for any change in state. In thisregard, the previously mentioned fast switching feature can further beutilized to periodically apply a short duration application of power,for example, a single half cycle (or multiple thereof) of AC power, toan otherwise powered off device or devices. This can be done for thepurpose of sampling a signature response for that half cycle (ormultiple thereof) to determine certain characteristics of the attacheddevice(s). For example, power may be supplied for a time intervalsufficient to obtain a load signature. It is expected that, in manycases, this may be accomplished on a cycle or subcycle basis, e.g., bysupplying a half cycle or full cycle (or other V2 cycle multiple) ofparts to take advantage of switching at zero crossings. This feature ispreferably performed in coordination with the aforementioned analysiscapability. During the initial analysis acquisition session, e.g. whenthe device is first plugged into a smart receptacle, and an analysis isperformed, the smart receptacle will sample the power signal applied toacquire the electrical current waveform (signature) associated with thenew device. The device can then be turned off by the smart receptaclemomentarily, and after a short wait period, the device is turned on forone half AC cycle (or other interval). During that one half AC cycle,the current waveform is again sampled, and a second “signature” isrelated to the device.

This signature can be used to examine the receptacle every so often asdesired when the power to the device is turned off by the smartreceptacles by applying a short duration of power and sampling theresulting waveform as previously described and analyzing the resultingsignature. This analysis can be used to determine whether the device isstill present, if the device remains in an off or idle state, or ifother devices are present, i.e., additional loads have been connected tothe smart receptacle being sampled. This is particularly useful indetecting if receptacle has attached power transformers, or converters,such as are commonly found on consumer electronics, and if they are idleor loaded. In this example, a cell phone charger, for example, could besampled when it is charging and when it is not charging a cell phone,and waveforms could be recorded for each of these states. When inoperation, the smart receptacles can then detect if the cell phone isconnected to the charger (which in turn is connected to the smartreceptacle) or if the cell phone is not connected. In either case, thecharger would remain connected to the smart receptacle. In the case ofthe cell phone not being connected to the charger, it is desirable tonot deliver power to the receptacle, thus reducing the quiescent load.

This load, although small, is significant when multiplied by manyhundreds of millions throughout the grid. A significant power savingsoverall can be realized simply by shutting down unused wall poweradapters. This same feature of the smart receptacle is useful for alarge class of attached devices. Some examples include: personalcomputers, laptops, etc., electric shavers, and nearly all rechargeableconsumer appliances charged with an external charger. Televisions andconsumer audio equipment are also examples of devices that can bepowered off completely when not in use, but that often have a smallquiescent power draw. In the US alone, it is estimated the averagehousehold has at least 10 such devices. If, for example, each of thosedevices draws 10 one-thousandths of an amp (10 milliamps), and there are100 million households (for example) the total potential unnecessaryload is 10 million amps (at 120 VAC)=1200 megawatts, resulting in asignificant carbon dioxide output.

In accordance with another aspect of the present invention, a localcircuit device such as a receptacle module communicates with acontroller via electrical power wiring of the premises. An associatedsubsystem includes an electrical device that receives power throughelectrical wiring of a customer premises via an electrical circuit and aswitch module, associated with the local circuit device, for controllingdelivery of power to the electrical device. The utility further includesa receptacle controller for controlling operation of the switch module.The switch module and the receptacle controller preferably communicatevia the electrical wiring using an internet communication protocol(e.g., UDP and/or TCP/IP) or use other protocols which a localcontroller (e.g., an internet connected device) can gateway and/or proxyto TCP/IP such that the switch module and/or a device plugged into thereceptacle of a switch module can communicate via TCP/IP. The subsystemcan be used to coordinate power delivery via the receptacle in relationto a larger power distribution system, e.g., the power grid.Alternatively, the subsystem can be used to allow for monitoring andcontrolling operation of the electrical device remotely, e.g., via theinternet.

The present invention can also be implemented in the context of a datacenter. Data centers often include a power strip including outletsassociated with two separate sources. For example, one such power stripproduct is being developed by Zonit Structured Solutions. The powerstrip can thus implement switching functionality as discussed above soas to provide redundant power supplies, e.g., for critical data devices.However, it will be appreciated that it will generally not be desirableto steal cycles from data devices and that switching will normally onlybe implemented in connection with power interruptions. Accordingly, heatbudget concerns are greatly reduced, and the fast power switchingfunctionality may not be necessary but could be implemented nonetheless,if practical.

In a residential, commercial or data center context, a controller cancommunicate with the receptacles by TCP/IP protocol, as discussed above.When using power lines for such communications, it is useful to providesome mechanism to avoid cross-talk. That is, because the power linesthat ultimately extend between multiple receptacles effectively define asingle electrical bus or interconnected circuits. Instructions from thecontroller intended for a first receptacle could be received by andacted upon by a second receptacle absent some mechanism to limit thetransmission of messages or to allow receptacles to discriminate asbetween received messages. An addressing mechanism for deliveringmessages to specific individual receptacles of a set of controlledreceptacles can resolve the issue within a given control domain. Amechanism to limit the transmission of messages between central domainscan resolve the issue between control domains. It is also desirable tolimit the transmission of messages via power lines so as to keep thepower waveform clean. This may be accomplished by signal cancellation orattenuation at the control point, e.g., a local controller, for a set ofpower receptacles. Specifically, the local controller is associated witha transceiver for inserting communication signals directed to thecontrolled outlets into a power line and receiving communication signalsfrom the receptacles via the power line. An attenuation or cancellationdevice can be provided external to this transceiver, i.e., between thetransceiver and the power network external to the controlled domain. Inthis regard, cancellation involves specifically eliminating particularsignals such as through use of an active cancellation signal, or passivefiltering, based on the signal to be cancelled. Attenuation relates toemploying a frequency dependent filter to selectively exclude thefrequency or frequencies used to communicate via the internal powerwiring from transmission to the power network external to the controlleddomain.

In addition, it will be appreciated that the control functionalitydiscussed above can be implemented at an electrical device rather thanat an outlet or other local circuit device (or at an intermediate unitinterposed between the electrical device and the outlet). That is, froma communications viewpoint, there is little distinction between thedevice and the outlet where the device is plugged in; communications canbe transmitted via the power lines all the way to the device. Thus, thesmart switch or other communication and control technology canalternatively be implemented by custom manufactured or retrofitteddevices. In the context of a data center, data may be accumulated andviewed (via an LCD or LED panel or web interface) at a power strip, anassociated controller or remotely. In this regard, the need foradditional cabling to support instruments (such as thermometers, airflowsensors, door lock sensors, light or humidity sensors, etc.) is reduced,thereby simplifying servicing, conserving rack space and enhancingcooling airflow.

According to a still further aspect of the present invention, anintelligent electrical outlet is provided. The outlet includes areceptacle for receiving a standard electrical plug so as to establishan electrical connection—between a device associated with the plug and apremises wiring system associated with the receptacle—and a digitalprocessor for controlling delivery of power via the receptacle. Forexample, the digital processor may be embodied in a circuit board thatcan be housed within a standard outlet housing, e.g., to execute thefast power switching functionality as described above. In this manner,intelligent monitoring and control can be implemented at the individualoutlet level or individual receptacle level of a power distributionsystem.

In accordance with a still further aspect of the present invention, apower distribution system is provided that allows for greater monitoringor control of power distribution, including control at the customerpremises level. The system includes a power grid for distributing powerover a geographic distribution area, one or more grid controllers forcontrolling distribution of power across the power grid and a number ofcustomer premises (local) controllers. Each of the customer premisescontrollers control delivery of power within a particular customerpremises based on communication between the customer premises controllerand at least one of the grid controllers. For example, the customerpremises controllers may be implemented at the customer premises leveland/or at the individual outlet level within the customer premises. Acustomer premise controller can be replicated for increased reliabilityand suitable means can be used to insure that the replicated controllerscooperate properly in how they manage the receptacles they control.Also, a local customer premise can have multiple controllers (each ofwhich can be replicated) that control different subsets of the set ofsmart receptacles in the customer premise. This may be useful in somescenarios such as a multi-tenant office building, for example. The localcontrollers can use the network address space or lists of networkaddresses or other means to specify which smart receptacles theycontrol.

This in conjunction with an appropriate link-level protocol (such asEthernet for example) allows all of the local premise controllers toco-exist and function on the same customer premise wiring network whencommunicating with the receptacles they control or each other. Anattenuation or cancellation device can be used as described previouslyto limit all of the customer premise local controllers and smartreceptacle transmissions to only the customer premise wiring. As can beappreciated, it is possible to use a variety of security methods, suchas used in TCP/IP and other network protocols, to insure that only anauthorized set of local controllers can control a desired set or sub-setof local smart receptacles. Further, it is possible to provide multipleuser accounts on each controller with separate privileges. These loginscan be managed using a variety of authentication, authorization andaccounting features such as are used to manage user accounts on avariety of modern operating systems, for example Linux, Unix, VxWorks,etc.

It is noted in this regard that the local controller (whetherimplemented at the outlet and/or elsewhere on the customer premises) mayexecute purely local policies, policies driven by external (e.g., grid)controllers, or combinations thereof. For example, the local controllermay control power delivery based on local policies concerning branchwiring current limits, security policies, safety policies, or otherpolicies not requiring communication with or coordination with a gridcontroller or other external controller. Conversely, the localcontroller may be utilized to execute a grid-based or other externalpolicy, such as a brownout operating mode. In still other cases, thelocal controller may make decisions based on both local and externalconsiderations. For example, a grid controller may instruct localcontrollers, on a mandatory or voluntary basis, to operate inconservation mode. Local controllers may then execute a conservationmode of operation in accordance with local policies, e.g., concerningwhich devices may be turned off or operated in reduced power mode orwhich devices have priority for continued operation.

In accordance with a still further aspect of the present invention, amethod is provided for addressing over-capacity conditions in a powerdistribution grid. The method includes the steps of identifying anover-capacity condition with respect to at least a portion of a powerdistribution grid and addressing the over-capacity condition bycontrolling power distribution at a level finer than the finestdistribution subdivision of the power distribution grid. In particular,the over-capacity condition relates to a condition potentially requiringreduction of power provided to standard residential and commercialcustomers, e.g., conditions that have conventionally resulted inblackouts or brownouts. In some cases, such conditions have beenaddressed by a rolling blackout, as discussed above, where a grid isdivided into a number of grid subdivisions, and power to these gridsubdivisions is sequentially interrupted to reduce the overall load onthe grid. The present invention allows for addressing such conditions ata finer and/or more flexible level than these network subdivisions. Inthis manner, individual residences, commercial clients, or any desiredset of customer premises can be managed as a group independent of gridtopology. For example, power distribution may be controlled at theendpoint receptacle and electrical distribution rather than the powerdistribution portion of the distribution network. As noted above, powerdistribution generally refers to transmission between a power plant andsubstations whereas electrical distribution refers to delivery from asubstation to the consumers. For example, in accordance with the presentinvention, power distribution may be controlled at the customer premiseslevel or even at the outlet level within a customer premises. Moreover,power distribution may be controlled by reducing the delivery of power,e.g., by eliminating certain cycles, or by interrupting powerdistribution. In this manner, blackouts or brownouts can be avoided orimplemented more intelligently so as to avoid the harm or inconvenienceassociated with such blackouts or brownouts.

In accordance with a still further aspect of the present invention, asystem is provided for controlling a device that is plugged into a smartoutlet. The system can be used in a variety of contexts, including datacenter control, as well as controlling electrical devices in aresidential or business environment. The system includes a localcontroller and one or more smart outlets. The local controller cancommunicate with a remote controller via a first protocol and with thesmart outlet via a second protocol the same or different than the firstprotocol. In this regard, the local controller can function as aprotocol gateway to translate messages between the first and secondprotocols. For example, the local controller may communicate with theremote controller via a wide area network such as the internet. Again,it should be appreciated that any method of implementing the TCP/IP WAN(wireless, cable, modem, ISPN, DSL, satellite, etc.) may be employed. Inaddition, the local controller may communicate with the smart outlet viapower lines, wirelessly or via another communications pathway. In thisregard, communications between the local controller and the smart outletare preferably conducted in accordance with a TCP/IP protocol adaptedfor the local environment. In one implementation, the local controlleris implemented in conjunction with a power distribution unit of a datacenter. The smart outlet may be implemented in conjunction with a datacenter power strip. In this manner, data center equipment can beconveniently controlled from a remote location. In addition, data centerdevices, such as temperature sensors, humidity sensors or door locksensors, can report to a remote location as may be desired.

In accordance with a still further aspect of the present invention, alocal controller can function as a communications gateway for multipleappliances, smart receptacles or combinations of appliances and smartreceptacles associated with the local controller. In this regard, thelocal controller can execute TCP/IP over power wiring functionality orother data protocol. The local controller can then gateway all localdevices to a WAN. In this manner, all local appliances can communicateto and be controlled via the WAN. Some examples of what this enablesinclude: allowing a smart refrigerator to order food from a market asnecessary; allowing a furnace to report via the WAN that it is leakingcarbon monoxide into the forced air; and an air conditioner can reportvia a WAN that the fan motor is about to fail.

The local controller can gateway such communications in at least thefollowing ways. First, and preferably from a standardization standpoint,such communications can be TCP/IP from end-to-end. The local controllerthus acts as a TCP/IP router (and power line transceiver). The localcontroller may also act as a firewall. In this case, both endpoints ofthe communication “speak” TCP/IP. Second, the local controller maygateway and proxy between TCP/IP and another communications protocol(over power wiring). Again, the local controller acts as a gatewayrouter and can act as a firewall. In this case, the appliance beingcontrolled speaks in its native communications protocol (which could beused to encapsulate TCP/IP) to the local controller and the localcontroller speaks TCP/IP (which, inversely, can be used to encapsulatethe appliance communication protocol) to the WAN.

The TCP/IP gateway provided by the local controller as discussed abovehas several functions. First the gateway provides universal and uniformTCP/IP WAN connectivity. All smart receptacles and electrical devicesconnected to them with suitable adapters or internal hardware cancommunicate via TCP/IP to a WAN (such as the internet) via the localcontroller. This can be done regardless of what protocol is used tocommunicate over the power wiring in the facility, but it is preferredto be via TCP/IP also. The TCP/IP communication functions offered by thecontroller are those which are commonly used to interconnect any twoTCP/IP networks. Some of which include the following:

1. Routing. TCP/IP Data transmissions from smart receptacles and deviceson the power-wiring network to the TCP/IP WAN are enabled and viceversa.

2. Network Address Translation. Only one public TCP/IP routable addresson the TCP/IP WAN is needed for complete connectivity.

3. Protocol Encapsulation. If one or more non-TCP protocols are used bysmart receptacles and/or devices on the power-wiring network, they canbe bi-directionally encapsulated and thereby enable end-to-endcommunication between the device on the power wiring network and anendpoint on the TCP/IP WAN. TCP/IP can be used to encapsulate theprotocol(s) used on the power wiring network and inversely the powerwiring network protocol can be used to encapsulate TCP/IP to areceptacle or device on the power-wiring network. The latter is possiblebut not a preferred method.

4. Proxy Server Function. If it is desired all devices on thepower-wiring network can be proxied by the TCP/IP proxy functionality ofthe controller. This may be a convenient way to communicate with andcontrol the receptacles and devices on the power-wiring network.

The gateway also provides security and privacy functionality. The TCP/IPgateway in the local controller also acts as a firewall to monitor andcontrol the data connections from the power wiring network smartreceptacles and attached electrical devices to devices on the TCP/IPWAN. The gateway can also be configured to control all connectionslocally between devices using the firewall. Policies can be set tocontrol, limit and report on this connectivity. In this way the privacyand security of the homeowner or facility owner can be safeguarded.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the present invention, and furtheradvantages thereof, reference is now made to the following detaileddescription, taken in conjunction with the drawings in which:

FIGS. 1A and 1B illustrate front and side views, respectively, of asmart outlet box in accordance with the present invention;

FIG. 2 is a schematic diagram of a smart outlet system in accordancewith the present invention;

FIG. 3 is a schematic diagram of a smart outlet system implemented in awide area network context in accordance with the present invention;

FIGS. 4A and 4B illustrate a power distribution grid utilizing smartoutlet technology in accordance with the present invention;

FIG. 5 is a flow chart illustrating a process for controlling electricaldevices utilizing a smart outlet system in accordance with the presentinvention;

FIG. 6 illustrates a smart outlet system in accordance with the presentinvention implemented in a data center context in accordance with thepresent invention;

FIG. 7 is a flow chart illustrating a process for controlling devices ina data center context in accordance with the present invention;

FIG. 8 is a schematic diagram of a controlled set of receptacles showinghow signals are inserted into power lines and prevented from beingtransmitted to external power lines; and

FIG. 9 is a schematic diagram showing GFCI circuitry in accordance withthe present invention.

FIG. 10 is a schematic diagram showing a alternate means of implementinga “cycle stealing” switch in accordance with the present invention.

DETAILED DESCRIPTION

The present invention is directed to intelligent local circuit devicesthat can control power delivered to an electrical device via a circuitand/or report information about or from an electrical device connectedto a circuit. This allows for remotely monitoring and/or controllingelectrical devices, including standard electrical devices that are notspecially adapted for such remote monitoring or control, which could beuseful in a wide variety of applications. In the following description,the invention is set forth in the context of standard NEMA or otherrecognized electrical standard (e.g., CEE, BS, etc.) electricalreceptacle outlets provided with logic for monitoring connected loadsand sampling power waveforms (e.g., electrical appliances and devices)and for selectively controlling power delivered via the outlets.Thereafter, certain systems for taking advantage of this functionalityare described. In particular, power grid distribution systems and datacenter equipment control and power distribution systems are described.It will be appreciated that circuit devices other than electricalreceptacle outlets and applications other than the noted power grid anddata center applications, are supported by the technology of the presentinvention. Accordingly, the following description should be understoodas illustrative and not by way of limitation.

The invention may be more fully understood by reference to FIGS. 1-4.Referring first to FIGS. 1A and 1B, front and side views, respectively,of an intelligent outlet in accordance with the present invention areshown. The illustrated outlet 100 includes two standard receptacles 102accessible through a faceplate 104. Each of the receptacles 102 includesa receptacle body 106 for receiving a standard electrical plug andestablishing an electrical connection between prongs of the plug andwiring 110 associated with the wiring system of the customer premises,e.g., a residence or business. The illustrated receptacle 100 furtherincludes a controller 108 mounted within the outlet housing 112 in theillustrated embodiment. For example, the controller 108 may be embodiedas an integrated circuit board. As will be discussed in more detailbelow, the controller 108 is operative for monitoring a loading withrespect to each of the receptacles 102 and controlling delivery of powerto the receptacles 106. For example, this may be done to classify anelectrical device connected via the receptacles 106 or to identify asafety hazard. Delivery of power to the receptacles 102 may becontrolled to alleviate a safety concern, to enhance efficiency of powerdistribution, to remotely control an electrical device connected to oneof the receptacles 102, or to address a potential or actual overcapacity condition of a power grid. The controller 108 may also beoperative for communicating with other controllers, e.g., within thecustomer premises, at a separate customer premises or with networkcontrollers outside of the customer premises. For example, suchcommunications may be conducted via power lines, wirelessly or via othercommunications pathways.

FIG. 2 is a schematic diagram of a power distribution system 200 inaccordance with the present invention. The illustrated system 200includes an electrical device 202 that is plugged into an electricalreceptacle 204. The receptacle 204 selectively receives power from apower source 208, such as an electrical grid, via a switch 206. Theswitch 206 may be located at the receptacle 204 or at a remote location,such as at a circuit breaker board or other location associated with acircuit for providing electricity to the receptacle 204.

In the illustrated embodiment, the switch 206 is operated by a processor212 based on monitoring of an electrical signal at the receptacle 204.For example, the processor 212 may be located at the receptacle, at aseparate location on the customer premises (e.g., a computer configuredto control a number of outlets) or at another location. In this regard,the signal at the receptacle 204 may be monitored to identify anelectrical signature that identifies the device 202 or the type of thedevice 202. It will be appreciated that different types of electricaldevices have different characteristics in relation to how they load theelectrical system. For example, an electrical pump may have a differentsignature than an electrical light. This signature may relate to thepower drawn, a time-dependent characteristic of the power drawn, orother cognizable signal characteristic from the power signal deliveredvia the receptacle 204. Alternatively, an intelligent device mayidentify itself to the receptacles, e.g., by transmitting a standardidentification code.

The nature of the signature may be determined theoretically orempirically. For example, heuristic logic may be used to learn andparameterize electrical signatures for different devices of interest.Such signature information can then be stored in a signature database214. Accordingly, the illustrated system 200 includes ananalog-to-digital converter 210 for digitally sampling the electricalsignal at the receptacle 204 and providing digital informationrepresentative of the signal to the processor 212. This digitalinformation is then processed by a signature recognition module 216 ofthe processor 212 to identify the signature. For example, the inputdigital signal may be processed by algorithms to determine a number ofparameters of the signal, which can then be compared to parametersstored in the signature database 214 to match the input signal to one ofthe stored signatures. It will be appreciated that the signatureinformation can also be used to determine a state of the device 202 orto detect an output from the device (e.g., in the event that the device202 is a sensor that provides an output signal).

An output from the signature recognition module 216 can then be used bya decision module 218 to control delivery of power to the receptacle204. In this regard, the decision module 218 may also use informationinput from a controller 220, which may be disposed at the outlet,elsewhere in the customer premises (such as a computer), or at anotherlocation. In one implementation, the controller 220 is in communicationwith the larger power distribution system, e.g., the power grid. Forexample, if the device 202 is recognized as a device that can functionat a reduced power level, the decision module 218 may operate the switch206 to reduce power delivery to the receptacle 204. In this regard, itis possible to “steal” a certain number or percentage of power signalcycles without unacceptably affecting the performance of certaindevices. In such applications involving frequent switching, the fastswitching functionality discussed above allows operation within theavailable heat budget, as will be discussed below. Appropriate switchingmechanisms are described in U.S. Provisional Patent Application Ser. No.60/894,842 and U.S. Patent Application Serial No. PCT/US2008/057140,which claims priority therefrom, and U.S. Provisional Patent ApplicationSer. No. 60/894,848 and U.S. Patent Application Serial No.PCT/US2008/057144, which claims priority therefrom, which areincorporated herein by reference. The decision module 208 may beprogrammed to implement such a power reduction by the customer or apower provider, such as a public utility.

In other cases, the controller 220 may direct the decision module 218 togo into a power saving mode. For example, this may occur when anover-capacity condition is identified with respect to the power grid ora portion of the power grid. In such cases, the decision module 218 mayreduce or eliminate power delivery to certain classes of devices.

As a further example, the signature recognition module 216 may determinethat the device 202 does not match any signature authorized for use atthe receptacle 204. In such cases, the decision module 218 may operatethe switch 206 to interrupt delivery of power from the source 208 to thereceptacle 204. Similarly, the decision module 218 may interrupt powerdelivery in the event of a potential short circuit, a potential shock orelectrocution, or other potential safety hazard event.

It will be appreciated that the system 200 may be used for a variety ofother purposes. For example, the processor 212 may operate the switch206 to turn on lights or operate other electrical equipment on aperiodic or random basis to create the illusion that the premises areoccupied and thereby discourage crime. In addition, the processor maymonitor the receptacle 204, for example, to identify activities when thepremises are supposed to be vacant, thereby identifying possible crimeor unauthorized use. Moreover, the processor 212 may be used to allowfor remote control of the receptacle 204, for example, to allow an ownerto remotely operate electrical devices via the internet or other WAN. Itwill be appreciated that the various functional components noted in thisdiscussion may be combined on a common platform or distributed acrossmultiple platforms (e.g., at the outlet, a separate customer premisesplatform or other platforms) in any appropriate manner.

FIG. 3 illustrates a system 300 in accordance with the present inventionfor enabling remote monitoring and/or control of multiple receptacles.In particular, the system 300 includes a number of smart receptacles302, which may be, for example, receptacles as discussed above inconnection with FIGS. 1A and 1B. The receptacles 302 communicate with alocal controller 304, which may be, for example, a computer or internetterminal located at the customer premises. For example, the smartreceptacles 302 and the local controller 304 may communicate via aninternet protocol (e.g., TCP/IP) or a proprietary protocol that isgatewayed to the WAN over electrical wires of the customer premises. Thelocal controller 304 can, in turn, communicate with a remote controller308 via a wide area network 306 such as the internet. In this regard,the communication between the local controller 304 and the remotecontroller 308 may involve wireless (e.g., IEEE 802.11, Wi-Fi, telephonyor other wireless) or other data network links. The remote controller308 may be operated by a private or public party. For example, theremote controller may comprise a computer used by an owner of thecustomer premises to remotely control the receptacles 302, a computermonitored by a security contractor to monitor activities at thereceptacles 302, a controller of the power grid operated to implementintelligent blackouts or brownouts or any other entity.

FIG. 4A illustrates a power distribution network 400 for intelligentlycontrolling power distribution. The illustrated network 400 includes anumber of customer premises 402 connected to a power grid 403. The powergrid 403 receives power from a number of power facilities 408, anddistribution of power across the grid 403 is controlled by a centralgrid control system 406 and, optionally, a number of regionalcontrollers 404, such as substations. As discussed above, each of thecustomer premises 402 may include a number of intelligent outlets. Theseoutlets may be controlled in response to instructions from the centralcontrol system 406 or regional controllers 404. Thus, for example, thecustomers may choose to or be required to install intelligent outletsthat operate in response to such instructions from the central controlsystem 406 or regional controllers 404 to reduce power consumption on aroutine basis or in the event of over-capacity conditions.

Though the control functionality is discussed in FIG. 4A in relation toa grid control system and substations, it will be appreciated thatcontrol messaging need not be via power lines and that such control isnot limited by power network topology. This is explicitly shown in FIG.4B. In this case, control messages are directed to individual customerpremises via a separate network such as the internet 411. In thismanner, a given set of instructions can be delivered to a subset ofresidences (shaded) independent of power network topology associatedwith substation 404. Moreover, as discussed above, instructions may beimplemented on a scale finer than individual residences, e.g., on anoutlet-by-outlet basis (as indicated by partially shaded residences). Inthis manner, for example, a brownout may be implemented intelligently,e.g., by interrupting power to non-critical devices and/or stealingpower cycles from appropriate types of devices.

FIG. 5 illustrates a process 500 for monitoring and controllingelectrical devices in accordance with the present invention. Thisprocess 500 will be described in relation to applications that enablemonitoring and remote control of electrical devices connected to smartoutlets as described above, including applications for allowing controlof electrical devices by the operator of a power grid. The illustratedprocess 500 is initiated by establishing (502) network policies relatedto power usage within the network. For example, such policies may beestablished by an electrical utility in order to address potential oractual overcapacity situations that have previously been addressed, forexample, by rolling blackouts or brownouts. It will be appreciated thatthese policies may be established in any way that is deemed useful bythe power provider. Some examples are provided below:

1. Efficiency Mode

In the efficiency mode, individual residences that are subject to thepolicy are instructed to reduce power consumption by a certainpercentage. This may be implemented at the residence by disablingselected devices and/or reducing power consumption by certain devices,as will be described in more detail below.

2. Brownout Mode

In the brownout mode, the highest loads (e.g., air conditioning,electrical heating, etc.) are identified and serially shut down forshort periods of time (e.g., 5-10 minutes) to reduce overall peak load.In order to avoid having all homes and business shut down such loads atonce, instructions may be sent to residences or executed at residencesin a random, pseudo random or otherwise time distributed manner. Forexample, a residence may be assigned an identification code by a randomnumber generator. Thereafter, instructions to execute the brownout modemay be sent out or executed on a time dependent basis as a function ofcode, e.g., at a given time, the brownout mode may be executed by allresidences having an identification that ends in the number “5.”Statistically, this can be accomplished in a way such that the peak loadwill be reduced by the needed percentage, but the impact to end users isminimized.

3. Blackout Mode

In the blackout mode, critical loads (e.g., refrigerators, lights,radios, radiant heating circulation pumps, etc.) can be identified andallowed on a full power or reduced power basis as appropriate.Non-critical items may be disabled.

It will be appreciated that many other modes of operation and associatedpolicies may be defined. In the illustrated process 500, once thenetwork policies have been established, local rules are established(504) for implementing the network policies. This optionalimplementation allows residential or business customers to have someinput, for at least some policies, as to how such policies will beimplemented. For example, the customer may define which appliances ordevices are critical for purposes of executing a brownout or blackoutpolicy. Moreover, a customer may be allowed to determine whether aprescribed energy reduction will be executed by disabling devices,reducing power drawn by devices or some combination thereof. Moreover,in certain implementations, consumers may be allowed to request timeperiods during which energy use will be reduced in order to achieve thepurposes of the policy at issue. Though it may not be possible, as apractical matter, to accommodate all such requests, some requests may beaccommodated at least to an extent, thereby reducing the impact onusers.

Additional local policies and rules may be established (506) to takeadvantage of the smart outlets. For example, a customer may choose tooperate in an efficiency mode at certain times or under certainconditions (e.g., while on vacation or when the premises are otherwisevacant). In addition, as noted above, a customer may wish to monitor thetypes of devices that are connected at individual receptacles or powerusage, for example, for security purposes. In this regard, the customermay wish to be notified of certain events, e.g., when a light is turnedon when no one is supposed to be present at the premises, to have athird party notified of certain events (e.g., a security or emergencyservice provider) or to prohibit certain uses (e.g., to prohibit use oflights, equipment, operation of electronic door locks or the like atcertain times or under certain conditions).

By way of example, the policies that may be implemented by a customerinclude the following:

1. Secure Travel Mode

In the secure travel mode, devices such as lights, radios and the likemay be turned on and off in a random, pseudo random or selected patternto make the home or business appear occupied. This may be preprogrammedor controlled, for example, by the home/business owner, from a remotelocation. In the latter regard, the devices may be controlled remotelyvia appropriate messages transmitted via the internet or anothernetwork. In addition, in the secure travel mode, an email alert may besent to a selected address in the event that a device is manually turnedon. Alternatively or additionally, a security or emergency serviceprovider may be contacted.

2. Living Mode

Using a local, web or other interface, an occupant can program when toturn on/off any device. For example, selected devices may be turned onor off in predetermined relation to a wake up time, departure for worktime, return from work time or bedtime.

3. Efficiency Mode

In efficiency mode, the system can automatically turn off or on orreduce power to lights or other devices during preset time periods or bymonitoring them to determine if their state is active or idle. Forexample, specified receptacles may be turned off during time periodswhere the residence is normally unoccupied or the residents are asleep.As an enhancement to this mode, devices can be monitored to determinewhen they have been manually turned off. When this occurs, the systemmay assume the occupant wants to turn the device back on manually andtherefore turn on the receptacle. It can be appreciated that the systemcan also store, sum and display realtime and/or historical power usagedata to inform user of energy usage details.

4. Safety Mode

In the safety mode, the user can select to disable certain receptaclesthat can be reached by small children or unused receptacles that are ina child's bedroom.

In addition to the various policies and rules that have been discussedabove, a number of advantages are provided by the system of the presentinvention. In particular, since the system can detect short circuits invery short times (e.g., in 1/60 of a second or less), the potential forserious electrical shocks is greatly reduced, not to mention the damagecaused to equipment by short circuits. Moreover, the ability to analyzethe power signature at the receptacles and then compare it to a standardor threshold has a number of benefits, including the following:

1. Quick Reaction to Shorts

All supported receptacles become “quick-acting” in responding to a shortcircuit and can be deactivated very quickly, thus enhancing safety topeople and equipment.

2. De-Rate Old Wiring or Breakers

Circuits can be “de-rated” if their wiring is old or otherwisedeteriorating. In this regard, the receptacle or set of receptacles on acircuit can be programmed to only allow a certain total current load,which can be set below the code and/or circuit breaker level(s). In thiscase, the central unit monitors the total current load on a branch andcan proactively control the load by switching off loads or reducingpower to certain receptacles. The central unit determines which outletsare connected on which circuit legs via power signature analysis. Theordering of what receptacles get switched off or reduced power can beset via policy as to the load type. This policy can be manually adjustedor overridden if desired or can be mandatory. This type of active powermanagement can help make the premises less fire prone. In this regard,it is noted that many home fires are caused by electrical wiringproblems. Accordingly, this type of system may be dictated by a codeand/or rewarded by insurance providers.

3. Wiring Leg Monitoring

This is done by monitoring the current near the input source via areceptacle near the power input to the house and monitoring the currentfarther down a circuit branch. The difference in power signatures asrecognized by the respective outlets will indicate if the wiring betweenthe outlets is not functioning properly. If this occurs, a number ofactions can be taken. For example, a receptacle can be instructed toswitch off the panel breaker for the circuit by inducing a short circuitfor a period of time, tripping the breaker or switch off for all thereceptacles on that branch circuit. If this is not appropriate to openthe breaker, an alert can be sent out via the communications pathwaysdescribed above. Such an alert can be sent out for any life safetycondition or other specified condition.

In the illustrated process 500, after the desired policies and ruleshave been established, loads are monitored (508) to identify loadsignatures. As discussed above, different devices may have differentsignatures that can be identified by analyzing the power signal or maycommunicate an identification code to the controller. In this manner,the device(s) plugged into a given outlet, or the general or specificclass of such devices, can be determined. A controller such as a localcontroller discussed above can develop (510) and update a load map forsupportive receptacles on the premises. Thus, at any given time, thelocal controller may store an estimate as to what devices or classes ofdevices are plugged in via what receptacles of the premises and how muchpower they are consuming individually and as a whole. It should be notedin this regard that only a subset of all receptacles on a given premisesmay be smart receptacles or that only a subset of receptacles (even ifall receptacles are smart receptacles) may be participating receptacleswith respect to a system implementation or with respect to individualpolicies.

Moreover, a physical security override mechanism such as, for example,the turnkey security mechanism described in PCT Application No.PCT/US2009/038,472, which claims priority from U.S. Provisional PatentApplication Ser. No. 61/039,716, (both of which are incorporated hereinby reference), may be employed to allow users “opt out” of some or allof the noted functionality with respect to an outlet, receptacle, or setthereof. Generally, this turnkey security mechanism provides a physicalmechanism, such as a key, that allows this functionality to be turned onor off with regard to the outlet(s) at issue. When the functionality isturned off, these outlets may revert to being conventional outletswithout network control. The key could be located at the localcontroller or at the outlet and could be a virtual key (e.g., a passwordenabled software override feature) or a physical key. In this manner,the user can override policies or other network controls, for example toalleviate security concerns. Optionally, certain functions, such as GFIfunctionality and/or utility based control for intelligentbrownout/blackout events, may be exempted from this turnkey securitymechanism override.

During operation of the system, a controller such as a local controllermay identify (512) a condition governed by policy. For example, in thecase of an external policy such as a change in operating mode dictatedby the grid power supplier, the condition may be identified based onreceipt of an instruction from the external source. For example, thelocal controller may receive a message from the electrical utilityprovider specifying transition to an efficiency mode or a brownout mode.Alternatively, the condition may be identified based on the occurrenceof a programmed policy condition. For example, if efficiency modeoperation requires that certain receptacles be turned off at certaintime periods, the beginning of such a time period may be identified as acondition governed by policy. As a still further alternative, theexistence of a condition governed by a policy may be identified based onanalysis of load information communicated from a smart receptacle to thelocal controller. For example, over loading of a circuit, manualoperation of a device in contravention of a policy, or other loadingbased conditions may be identified.

Upon identification of such a condition a controller such as the localcontroller may access (514) rules for implementing the relevant policy.Thus, if the electrical utility provider specifies a conservation modeof operation, local rules may be consulted to implement the requiredenergy usage reduction in accordance with customer preferences.Similarly, during secure vacation mode operation, if an electricaldevice is manually operated, the owner or a security or emergencyservice provider may be contacted according to rules defined by theowner. It can be appreciated that both the local premise and remote gridcontroller can keep a record of when policies are set and actions thatare taken to enforce those policies by the system. These logs may thenbe used as decision criteria for policies themselves. This enables thesystem to record and act on various kinds of historical data. In anyevent, the rules are applied (516) in relation to all supportedreceptacles or a specified subset thereof so as to give effect to thedesired policy. Specifically, instructions may be transmitted (518) tothe affected receptacles by the local controller. These instructionsmay, for example, cause a receptacle to be turned on, to be turned offor to operate in a reduced power usage mode. The smart receptacle thenoperates to execute (520) the instructions.

In this regard, as noted above, the smart receptacle may include a fastoperating switch operable in conjunction with a traditional mechanicalrelay as discussed above. This switch and associated relay can beoperated to turn the receptacle on, to turn it off or to steal cyclesfrom the power signal. In the last regard, the switch can be controlledby analog or digital devices to execute such switching at or near a zerocurrent flow point of the power signal so as to reduce the potential forarcing. Moreover, such a switch is preferably designed to functionwithin the heat budget of the application environment. In this regard,it is noted that receptacle boxes may, in some cases, be surrounded byinsulation such that heat dissipation is largely limited to heattransfer across the face plate. The present invention can be implementedwithin the associated heat budget. However, if necessary, face platestructures can be modified to provide a larger heat budget for operationof the system. For example, the associated electrical boxes can extendsome distance from the wall so as to provide greater heat transfersurfaces or active heat dissipation, e.g., by miniature fans, can beemployed.

Another application where it may be desired to control electricaldevices in accordance with a policy or to allow for remote control ofsuch appliances is the data center environment. In this regard, it isoften useful to be able to control power to electronic data processingequipment. This capability is especially useful for situations where theequipment is densely packed as in a data center that is far away fromthe user who desires to control the equipment.

FIG. 6 illustrates a system 600 for enabling such control in a datacenter environment. In particular, the illustrated system 600 includes anumber of data center devices 601-609. These devices 601-609 include anumber of data devices 601-606 such as servers, storage devices and thelike. In addition, the devices 601-609 include a number of sensors607-609 such as temperature sensors, humidity sensors, cage or cabinetdoor lock sensors and the like. The devices 601-609 are typicallymounted in one or more two- or four-post equipment racks data centerracks.

In the illustrated embodiment, the devices 601-609 are plugged intoreceptacles 612, 634 and 644 associated with a number of power strips610, 630 and 640. As will be discussed in more detail below, thesereceptacles 612, 634 and 644 may be smart receptacles as generallydescribed above.

The power strips 610, 630 and 640 are connected by power lines to alocal controller 650. In this case, the local controller 650 may bebuilt into a data center power distribution unit such as marketed byZonit Structured Solutions. Generally, the power distribution unitincludes a number of output ports 654 for outputting power from powersources 660 to the power strips 610, 630 and 640. The power distributionunit may be associated with multiple power sources 660 such as an Asource and a B source so as to provide redundant, fail-safe power tocritical equipment. In this regard, different ones of the output ports654 may be associated with different ones of the power sources.Moreover, certain equipment may have connections to multiple powerstrips, as generally indicated in phantom by redundant power strips 620,so as to provide fail-safe operation. In this regard, such criticalequipment may be equipped with multiple power cords or an appropriatecord assembly with a fast-switching unit may be provided as described inU.S. Provisional Patent Application Ser. No. 60/894,842, and U.S. PatentApplication Serial No. PCT/US2008/057140, which claims prioritytherefrom, which are incorporated herein by reference.

The illustrated system 600 includes a number of elements for enablingremote and/or policy based operation of the devices 601-609.Specifically, the local controller 650 includes a processor 655 such asa single board computer for executing local controller functionality asdescribed above. In particular, the processor 655 enables wired orwireless communication between the local controller 650 and a remotecontroller 670 via a network interface 680. The processor 655 alsoenables communication between the local controller 650 and the smartreceptacles 612, 634 and 644. Such communications between the localcontroller 650 and remote controller 670 may be conducted via theinternet using a standard internet protocol involving TCP/IP protocoland utilizing TCP/IP and UDP packets. Communications between the localcontroller 650 and the receptacles 612, 634 and 644 are also preferablyconducted in accordance with a TCP/IP protocol and may be adapted forthe local environment. In this regard, the communications between thelocal controller 650 and the receptacles 612, 634 and 644 may beconducted via the power lines, wirelessly in accordance with an IEEE802.11 protocol or in any other appropriate fashion. It will beappreciated that customized messaging may be provided in this regard toaccomplish the purposes of the system 600. Accordingly, the processor655 can function as a protocol gateway to translate between the protocolfor communications between the remote controller 670 and the localcontroller 650 and the protocol used for internal messaging between thelocal controller 650 and the receptacles 612, 634 and 644. Devices canbe plugged into the smart receptacles and use the controller as agateway to the data center LAN (instead of or in addition to the WAN).

In the illustrated implementation, communications between the localcontroller 650 and the receptacles 612, 634 and 644 are conducted viathe power lines therebetween. This is advantageous in that dedicatedcommunications lines are not required as is problematic in a data centerenvironment due to the complexity of additional wiring and potentialinterference with cooling airflows. In this regard, each of the outputports 654 of the local controller 650 may be associated with a powerwire communications interface 651-653. These interfaces 651-653 areoperative to induce messaging signals in the power lines as well as toremove incoming messaging signals from the power lines so as to provideeffective electrical isolation of the different communication pathways.Similar power line messaging interfaces 611, 631-633 and 641-643 areprovided in connection with the power strips 610, 630 and 640 for thesame reasons.

Each individual receptacle of a power strip may be controlledindependently or all receptacles of a power strip may be controlled as agroup in accordance with the present invention. Thus, in the illustratedsystem 600, all of the receptacles 612 of the strip 610 are associatedwith a single communications interface 611. Similarly, all of thereceptacles 612 of the strip 610 may be associated with a common logicalelement for monitoring electrical signatures or receiving messages fromthe devices 601-603.

By contrast, each receptacle 634 and 644 of the power strips 630 and 640is associated with its own independent communications interface 631-633and 641-643 in the illustrated embodiment. For example, each receptacle634 and 644 may have dedicated wiring or the signals transmitted throughthe power wiring may be multiplexed with respect to the individualreceptacles (e.g., time division multiplexed, frequency divisionmultiplexed, code-division multiplexed, etc.). In this manner, thedevices 604-609 associated with the receptacles 634 and 644 can beindividually controlled, and the devices 604-609 can independentlymessage the local controller 650 and intern, in turn, the remotecontroller 670. In the latter regard, it will be appreciated that it maybe desired to provide messaging to the remote controller 670 based onoutput from the sensors 607-609.

Alternatively, a single transceiver for each power source (e.g., A and Bsources) may be utilized to induce signals in the associated wiring anda single signal canceller or attenuator, as discussed above, may beutilized to substantially prevent transmission of communications toexternal power lines. This is generally shown in FIG. 8.

In particular, FIG. 8 shows a control system 800 for a set ofreceptacles defining a controlled domain. The receptacles may include anumber of receptacle outlets 802 (typical for home or businessenvironments) and/or a number of plug strips 804 or adaptors (typicalfor data center environments) that may be arranged in one or more branchcircuits 806.

The receptacles are controlled by a local controller 808, which may be,for example, embodied in a personal computer (typical for home orbusiness applications) or in a single board computer incorporated into apower distribution unit in a data center. The local controller uses atransceiver 810 to insert signals into the main 812 and branch circuits806 for communication to the receptacles and to receive signals from thereceptacles. A signal isolation device 814, which may be a signalcanceller or a signal attenuator as described above, substantiallyprevents transmission of these signals to external (outside of thecontrolled domain) power lines 816. This structure may be replicated forA and B power sources in a data center. It will be appreciated that thusdisposing all of the controlled receptacles on a single waveguide (ortwo waveguides in the case of a data center with A and B power sources)is a cost effective implementation. Communications with separatereceptacles can be distinguished by use of an appropriate addressingscheme.

FIG. 7 illustrates a process 700 that may be implemented in connectionwith operation of the present invention in the data center context. Theprocess 700 is initiated by establishing (702) rules for devices orclasses of devices. For example, these rules may define preferences forpowering up or powering down devices, establish groups of devices to becontrolled collectively, determine who may access devices and at whattimes, etc. The process 700 further involves developing (704) a map ofoutput/outlet pairings. In this regard, it is possible to identifydevices or classes of devices based on a signature analysis as describedabove. Alternatively, a data center user may define what devices areconnected to what receptacles of what power strips and what power stripsare attached to what outlet ports of the power distribution units. Forexample, in this manner, the user can define groups of devices that willbe operated collectively (e.g., by plugging the devices into a powerstrip that is operated as a unit) and can specify critical devices forfail-safe operation. Such operation can then be executed simply byplugging the devices into the correct outlets of the correct powerstrips and plugging the power strips into the correct output ports ofthe power distribution unit. Execution of this power structuring may befacilitated by way of appropriate indicators, such as LEDs or smalldisplay units provided on the power strips and/or the power distributionunit. In this manner, the devices can be easily plugged (706) intoappropriate outlets.

The power strips or the individual receptacles then receive (708) aninput from the device or the local or remote controller. For example, anoperator of a remote controller unit may choose to power down or powerup a device or set of devices. An appropriate message is transmittedfrom the remote controller to the local controller, and this is in turncommunicated from the local controller to the power strip or receptaclevia the power wiring as discussed above. Alternatively, a signal, suchas a power signal for signature analysis or a sensor output signal, maybe received at the receptacle from one of the devices and communicatedto the local controller (and, if appropriate, to the remote controller).Any such input is then processed (710) using the noted map andappropriate rules. Thus, for example, an instruction from a remotecontroller to power down certain devices can be executed by consultingthe map to identify the outlets associated with the appropriate devicesand then communicating a power down signal to those receptacles.Similarly, a signal from a device such as a sensor may be interpreted byconsulting the map to determine what sensor transmitted the signal andthen accessing and applying the appropriate rules for processing thesignal.

In addition, the current interrupting ability of the receptacledescribed above permits using a transformer for sensing unbalancedcurrent in the load and interrupting the power delivery to the load incertain conditions. This feature is generally similar to common groundfault circuit interruption (GFCI) devices. It differs in that itutilizes the general purpose disconnect relay for the actualdisconnection means in the event an unbalanced current condition exists.It also differs in that the detection and decision to disconnect is notperformed in the same way as a traditional GFCI, in that themicroprocessor control used for the signature detection also has theability to analyze the current sense data from the dual purposetransformer and in doing so can filter out unwanted or alias currenttransients. This can result in fewer GFCI interruptions on events notactually attributable to real ground fault events. This condition ingeneral-purpose GFCI circuits is generally annoying and has resulted inthe less than enthusiastic reception of GFCI receptacles. Because theSmart Receptacle already has the processor embedded, much betterresolution on decision-making can be achieved, and thus fewer falseinterruptions initiated.

Referring to FIG. 9, a dual-purpose wound transformer 902 is added inthe current path, similar to traditional GFCI, and the sensed current“differential” is amplified by the high gain differential amplifier 901.The signal is presented to the Sense and Control Module 903 where ananalog to digital (A to D) converter converts the incoming analog signalto a digital signal. The data is processed on an interrupt basis in themicroprocessor. If any data appears at the output of the ladder A to D,the processor stops what it is doing and begins analysis of the incomingdata stream from the GFCI sense transformer. At this point signatureanalysis algorithms similar to the algorithms used for general currentload analysis are applied to the incoming data. If an event is deemed tobe a probable GFCI triggering event, the power control relays 940, 950are energized, thus in turn disconnecting the AC power source from eachof the load receptacles 907, 908. Since the current sense is in theprimary power path, both relays must be energized. The event is recordedtemporarily in the sense and control module 903 and sent to the CentralCommand Processor via the current transmitter 909. The event data isalso forwarded to the central command processor for additional analysis.The Central Command Processor can determine if the event data was falseor true and act accordingly, or it can wait for user intervention andsubmit a reset. At any time, either the Central Command Processor, or alocal user can reset the GFCI interruption condition. This can beaccomplished by either receiving a command from the Central CommandProcessor via the Current Receive Modulator 909 or from a manual resetbutton on the receptacle 906 by direct user intervention.

Power can be momentarily restored to one receptacle at a time. If theGFCI event still exists, a determination can be made which receptacle isresponsible at this time, and the associated LED 910 or 911 can beilluminated and/or flashed.

In addition, the incorporation of Light Emitting Diodes (LEDs) 910, 911allows other useful functions to be included in the Zonit SmartReceptacle. These LEDS 910, 911 can be controlled from the CentralCommand Processor. The user interface there can initiate severalfunctions using the LEDs 910, 911 located adjacent to each of thereceptacles 907, 908. Some of the functions include, but are not limitedto:

Indication of Ground Fault condition

Indication of Over Current condition

Indication of location of the circuit

Indication of all receptacles on a given circuit branch

Night Light

The LEDs 910, 911 are connected to the Sense and Control Module 903. Itreceives information either locally from the current sense coils in therelays 940, 950 from the Current Sense Transformer 902, the local manualreset button 906, or from the Central Command Processor via the CurrentReceive Modulator 909. The various information associated with the LEDfunctions is analyzed by the Sense and Control module and theappropriate LED 910 and 911 is illuminated or extinguished as needed.The LEDs 910, 911 are high illumination types, as much as 1 watt each.For general purpose annunciation needs, the Sense and control Module 903can pulse width modulate the power to the LEDS 910, 911 to provide a lowlevel output of light, for example, an “indicator light” level ofoutput. For Night Light operation, a higher level of output can beinitiated, as much as a continuous on state (no modulation). The LEDscan also be modulated in a visible pattern to indicate information tothe end user.

FIG. 10 illustrates a possible method of electronically providing thesingle cycle “stealing” function mentioned earlier. Instead of aconventional power switch, e.g. relay or triac or other semiconductordevice, the principal described here allows the AC power to be shut offfrom the load 1060 by induction rather than switching. The means bywhich this works is via a saturable iron reactor, or inductor (1000). Acombination of two effects is utilized to achieve the removal of eachhalf cycle or multiples thereof. The first effect is that of a largeinductor in series with the AC power delivery to the load 1060. If thisinductor, or reactor as it is referred to in this context, is acting asa pure inductor, the AC to the load 1060 will be restricted by thereactance of the inductor winding 1140. If the inductor core issaturated by a DC bias to a second winding 1120 via a switch 1010, thecore will no longer operate as an inductor, but will appear more as alow impedance short, thus allowing nearly all of the applied AC voltageto pass through the switch winding 1140 and to the load 1060. This wouldbe the normal condition of the inductor switch.

When a command to steal a half cycle is received via the modem 1050 andis prepared by the control logic 1040, the control logic sends a gatingsignal to the switch 1010 which in turn removes power from the coresaturation winding 1120. This allows the field in the core to becounteracted by the potential rising of a magnetic field in the switchwinding 1040, and throughout the half cycle of the AC, the switchwinding 1040 appears as an inductor, thus applying a significantreduction of the current delivered to the load 1060. To further aid thenegation of the power delivery to the load 1060, the control logic 1040sends a programmed set of values to the D to A 1030, which in turngenerates a bias analog signal that is amplified by amplifier 1020. Thisamplified signal is introduced into the third winding 1100 of thesaturable iron reactor 1000. This signal drives the magnetization of thecore in the opposite direction of the naturally occurring magnetizationof the switch winding 1140, and in effect cancels out the potential forcurrent flow in the switch winding 1140.

At the completion of the half cycle, the control logic 1040 returns thepower to the DC bias winding 1120, thus saturating the core, and removesthe bias signal from the bias winding 1100. At this state, the switchwinding is now back on with very little inductance and supplying fullcurrent to the load. This state will remain until the control logic 1040determines it is appropriate to “steal” another half cycle.

It should be appreciated that the inventors are aware of the size andweight of using conventional reactor technology to restrict the desiredfrequency and currents associated with the intent of this invention. Itshould also be appreciated, that by applying the dual mode control, anduse of modern materials, it may be possible to reduce the size andweight to an acceptable level.

In the forgoing description, certain functionality is reference eitherin relation to a data center or a home/office environment. It should beappreciated that the functionality described for the data centermonitoring and control is directly applicable to the home and officepower distribution model, and vice-versa. Moreover, these examples arenot intended to limit the invention to any particular environment.

The foregoing description of the present invention has been presentedfor purposes of illustration and description. Furthermore, thedescription is not intended to limit the invention to the form disclosedherein. Consequently, variations and modifications commensurate with theabove teachings, and skill and knowledge of the relevant art, are withinthe scope of the present invention. The embodiments describedhereinabove are further intended to explain best modes known ofpracticing the invention and to enable others skilled in the art toutilize the invention in such, or other embodiments and with variousmodifications required by the particular application(s) or use(s) of thepresent invention. It is intended that the appended claims be construedto include alternative embodiments to the extent permitted by the priorart.

What is claimed is:
 1. A power distribution system, comprising: a powergrid for distributing power over a geographic distribution area; one ormore grid controllers for controlling distribution of power across saidpower grid; and a number of customer premises controllers, each forcontrolling delivery of power within a particular customer premisesbased at least in part on communication between said customer premisescontroller and at least one of said grid controllers, wherein saidcustomer premises controller controls delivery of power within saidparticular customer premises such that a first electrical device of saidpremises is operated in one of the following states: i) a first statewherein the first device is operated at its normal operating power; andii) a second state wherein the first device receives no power; saidcustomer premises controller further controlling delivery of powerwithin said particular customer premises such that a second electricaldevice of said customer premises, the same as or different than saidfirst electrical device, is operated in the following state: iii) athird state, different from said first and second states, wherein saidsecond device receives a power signal that has been modified such thatsaid second device receives some power that is less than its normaloperating power.
 2. A system as set forth in claim 1, wherein saidcustomer premises controller controls said delivery of power based ondefined polices including local policies specific to said customerpremises.
 3. A system as set forth in claim 2, wherein said definedpolicies include grid policies communicated from at least one of saidgrid controllers.
 4. A system as set forth in claim 3, wherein said gridpolicies are executed in accordance with local policies.
 5. A system asset forth in claim 2, wherein said defined policies include a firstpolicy set implemented with respect to a device without regard to whatoutlet is utilized.
 6. A system as set forth in claim 5, wherein atleast one of said customer premises controllers is operative to identifysaid device or type of device based on analysis of a power signaldelivered to said device.
 7. A system as set forth in claim 1, whereinsaid customer premises controllers are associated with individualelectrical receptacles of said customer premises.
 8. A system as setforth in claim 1, wherein said defined policies include a second policyset involving controlling a time where power is delivered via one ormore outlets independent of any communication between said custompremises controllers and any of said grid controllers.
 9. A system asset forth in claim 1, wherein said defined policies include a secondpolicy set involving monitoring an operating environment of a device orcircuit.
 10. A system as set forth in claim 9, wherein said operatingenvironment relates to a status of recharging of said device.
 11. Asystem as set forth in claim 9, wherein said operating environmentrelates to a deterioration of said circuit.
 12. A system as set forth inclaim 9, wherein said operating environment relates to a potentiallyhazardous condition.
 13. A system as set forth in claim 1, wherein saidsystem further includes logic for monitoring the operation of a deviceor circuit over time to develop a policy.
 14. A method for powerdistribution, comprising: providing a power distribution systemincluding a power grid for distributing power over a geographicdistribution area, one or more grid controllers for controllingdistribution of power across said power grid and a number of customerpremises controllers, each for controlling delivery of power within aparticular customer premises; and operating said customer premisescontrollers to control delivery of power within said particular customerpremises such that a first electrical device of said premises isoperated in one of the following states: i) a first state wherein thefirst device is operated at its normal operating power; and ii) a secondstate wherein the first device receives no power; said customer premisescontroller further controlling delivery of power within said particularcustomer premises such that a second electrical device of said premises,the same as or different than said first electrical device, is operatedin the following state: iii) a third state, different from said firstand second states, wherein said second device receives a power signalthat has been modified such that said second device receives some powerthat is less than its normal operating power.
 15. A method as set forthin claim 14, wherein said customer premises controller controls saiddelivery of power based on defined policies including a first policy setthat includes a policy specific to said customer premises.
 16. A methodas set forth in claim 15, wherein said first policy set includes a gridpolicy communicated from at least one of said grid controllers.
 17. Amethod as set forth in claim 16, wherein said grid policy is executed inaccordance with a local policy.
 18. A method as set forth in claim 15,wherein said first policy set is implemented with respect to a devicewithout regard to what outlet is utilized.
 19. A method as set forth inclaim 18, wherein at least one of said customer premises controllers isoperative to identify said device or type of device based on analysis ofa power signal delivered to said device.
 20. A method as set forth inclaim 15, wherein said defined policies include a second policy setinvolving controlling a time where power is delivered via one or moreoutlets independent of any communication between said custom premisescontrollers and any of said grid controllers.
 21. A method as set forthin claim 15, wherein said defined policies involve monitoring anoperating environment of a device or circuit.
 22. A method as set forthin claim 21, wherein said operating environment relates to a status ofrecharging of said device.
 23. A method as set forth in claim 21,wherein said operating environment relates to a deterioration of saidcircuit.
 24. A method as set forth in claim 21, wherein said operatingenvironment relates to a potentially hazardous condition.
 25. A methodas set forth in claim 14, wherein said customer premises controllers areassociated with individual electrical receptacles of said customerpremises.
 26. A method as set forth in claim 14, further comprisingmonitoring the operation of a device or circuit over time to develop apolicy.